Working Long Hours Makes Us Drink More

June 7, 20151,697 Views

After a busy day at work, perhaps you head down to the pub to have a pint with your flatmates. Or maybe it’s an evening of sake and karaoke with the boss. Or pitchers of margaritas at your office park’s fast-casual restaurant. Work and alcohol: wherever we are, they seem to go together like start-ups and beer carts.

In moderation, there’s nothing wrong with that. But what about when it becomes a problem? Marianna Virtanen of the Finnish Institute of Occupational Health and colleagues found that people who log long hours are about 12% more likely to become heavy drinkers.

It’s just the latest in a series of studies she’s conducted on the negative health effects of overwork. “We have shown associations with impaired sleep and depressive symptoms,” she writes, via email. Another study showed an association between long hours and Type 2 diabetesin low income workers. And other research has found a dramatic correlation between overwork and heart disease.

In the study on excessive drinking, she and her colleagues took data from 61 different studies to create a dataset of over 330,000 workers across 14 countries. “We found that working more than 48 hours a week was associated with increased risky alcohol use,” explains Virtanen. “We defined risky alcohol use as more than 14 drinks per week for women and more than 21 drinks per week for men.”

Specifically, they found that people who worked long hours were, in general, 11% more likely to be heavier drinkers than those who worked normal hours. But just based on that association, they couldn’t be sure that long hours had actually caused the increased drinking. So they identified a cohort of their dataset that was logging long days, but had normal amounts of drinking, at the beginning of their dataset’s time period, and then tracked how those people were doing six years later. They found they were 12% more likely to have started drinking excessively. However, Virtanen notes, “this is an observational study, so we cannot completely make causal assumptions of the relationship between long working hours and alcohol use.”

A cultural aside: as an American, I found their definition of “risky” drinking to be rather generous. After all, the CDC says anything more than 8 weekly drinks a week for a woman or 14 for a man, is too much. This is just one of those things about which Europeans are a little more relaxed. For instance, Britain’s NHS advises women to stick to 2-3 units per day and men to 3-4 units per day — which would translate to 14-21 per week for women, and 21-28 for men. (Cheers, mate!)

But note that despite different countries’ different attitudes toward alcohol, and the fact that Virtanen’s data came from over a dozen countries, she did not see any differences between North America, Europe, Australia, or Asia: people everywhere were similarly likely to start drinking more as a result of pulling long hours.

The research team also found no differences between women and men, Virtanen explains: “Although women were less often risky drinkers than men (which has previously been shown in many other studies as well), the association was similar: if a woman worked long hours, her risk to develop unhealthy alcohol use habit was increased compared to a woman who worked standard hours.”

But maybe, to you, that sounds like a modest risk — nothing to write home about, or rather, head home over. If so, consider some of the other findings Virtanen has uncovered.

Is this dramatic change just because of increased stress? Or is there something else going on? Virtanen told me the mechanisms themselves haven’t been studied, so they can’t be entirely certain about which factors are involved. “We think stress might be one of them; poor recovery, poor sleep and symptoms of distress which can all contribute to heart diseases. Then there are lifestyle factors such as sedentary work and leisure time, unhealthy diet, alcohol use, and smoking. People who work long hours may in general have a lifestyle which involves poor self-care; for example they may be reluctant (or don’t have time) to see a doctor.”

Eventually, this physical wear and tear takes a toll on the brain. In yet another piece of research, Virtanen and team found that overwork hurts your brain in the long term. “We examined the association between long working hours and cognitive function and found a small decrease in a reasoning score [after] 5 years among those who worked long hours,” says Virtanen. “This finding may relate to cardiovascular health since it is known that cardiovascular health affects cognitive function.”

Looking for a loophole, I asked Virtanen if there was any difference, health-wise, in pulling late nights at the office and working from home. Does it still count as “overwork” if it’s just another hour or two of email after dinner? She’s not sure. “At the moment, we only have this large picture of the topic. Unanswered questions are: how long does one need to work overtime until there are harmful health effects? Is it harmful if you only have busy peaks of overwork every now and then? What if you enjoy your work and it’s highly rewarding? We hope we will get answers to these questions in our future studies.”

In the meantime, the best advice is the advice too many of us ignore: leave work at 5, and get thee to a gym.

Sarah Green is a senior associate editor at Harvard Business Review. Follow her on Twitter at @skgreen.